Stanford Research Systems SIM983, Operation And Service Manual

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1.6 SIM Interface 1 – 9
currents of digital control signals and the power supplies, whereas
the input voltage and the output voltage reference to Ground 2 (Sec-
tion 2.1.2). When operating in the SIM900, the three grounds are
tied together in the SIM900 Mainframe. Grounds 1 and 2 are con-
nected through back-to-back Schottky diodes, so they cannot be more
than
∼
± 0
.
35 V apart. The three ground lines should be separately
wired to a single, low-impedance ground source at the power supply.
1.6.2.2 Serial settings
The initial serial port settings at power-on are: baud rate 9600, 8 bits,
no parity, 1 stop bit, and no flow control. The baud rate of the SIM983
cannot be changed. Flow control is not implemented in the SIM983.
The parity may be changed with the
PARI command.
SIM983 Scaling Amplifier